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Objetivo. Conocer el estado serológico de hembras bovinas a IBR, DVB, leucosis, leptospira y Neospora caninum en el departamento de Santander, Colombia. Materiales y métodos.  Se realizó un muestreo por conveniencia en 460 fincas ganaderas de 23 municipios de Santander (Colombia), los sueros  colectados fueron analizados mediante diferentes kits comerciales de ELISA siguiendo las instrucciones del fabricante. Resultados. En todas las enfermedades estudiadas se encontraron animales seroreactores, correspondiendo la prevalencia general a Leucosis 21.8%, Leptospira 26.1%, DVB 29.7%, IBR 48.2% y Neospora 63 %. Conclusiones. En el departamento de Santander las enfermedades analizadas se encuentran en la población bovina con prevalencias que fluctúan entre medio a alto, lo cual requiere medidas de control oficial.

Background: The brilliant cresyl blue (BCB) staining is a non-invasive test to select the best-suited oocytes for embryonic development. This makes it a useful tool to select best-quality oocytes at the times of the year when there is forage restriction. Objective: To evaluate the effect of seasonality on the nuclear maturation and quality of oocytes selected by the BCB test. Methods: The cumulus-oophorus complexes (COCs) were obtained in summer and winter of 2010 and 2011. Selected COCs were maintained for 90 min at 38.5 °C in a CO 2 incubator, in TCM 199 medium containing 10% fetal bovine serum and antibiotics, and supplemented with 26 µM brilliant cresyl blue. Afterwards, they were divided according to the ooplasm staining (BCB + -blue; BCB − -unstained). Subsequently, COCs were matured for 22 h. Nuclear maturation was evaluated at 22 h of culture. Results: The proportion of BCB − oocytes was higher in the winter of 2010, but there was no increase in this group in the winter of 2011. The percentage of oocytes that reached metaphase II was higher in control and BCB + groups in relation to oocytes from BCB − group. Conclusion: The season of the year influences the percentage of oocytes best suited for embryonic production in situations in which

Titulo en español: Clonación de embriones bovinos a partir de células somáticastitulo en ingles: Cloning bovine embryos from somatic cellsResumo: No presente artigo revisa-se dedicadamente a literatura do tema da clonagem tentando levar o leitor paulatinamente através dos avanços da técnica até alcançar as mais novas alternativas propostas pelos cientistas, e incluindo os erros mais comumente acontecidos nelas. A finalidade é mostrar o amplio panorama que tem aberto esta biotecnologia para a humanidade toda.Palavras chave: Transferência nuclear, fissão, paraclonagem, clonagem verdadeira, genoma mitocondrial.Resumen: En el presente artículo se revisa detenidamente la literatura en el tema de clonación, intentando llevar al lector paulatinamente a través de los avances de la técnica hasta alcanzar las más nuevas alternativas propuestas por los investigadores, incluyendo los errores más comúnmente cometidos. La finalidad es mostrar el amplio panorama que a abierto esta biotecnología para la humanidad.Palabras clave: Transferência nuclear, fissão, paraclonagem, clonagem verdadeira, genoma mitocondrial.Abstract: The present article provides a review of the pertinent literature on the topic of cloning. It aims to take the reader gradually through the advances made so far regarding the technique, to the newest alternatives proposed by researchers, including the most commonly committed errors, to unveil the broad panorama this biotechnology has opened up for humankind.Key words: Nuclear transfer, fission, paraclone colony, true cloning, mitochondrial genome.

It has been shown that phosphatidylinositol 3 kinase (PI3K) participates in oocyte maturation by regulating the activity of important reactions related to the resumption of meiosis and energy metabolism. Changes in the enzyme activity caused by in vitro conditions may impair important events of oocyte maturation and consequently the production of blastocysts. The study aimed to verify the effect of the addition of wortmannin (a specific inhibitor of PI3K) to the in vitro maturation medium on nuclear and cytoplasmic maturation of bovine oocyte, as well as on the production of blastocysts. Cumulus-oocyte complexes (COCs) were matured in vitro in medium supplemented with FCS and 0 (control) or 20 nM of wortmannin and then fertilized and cultured in vitro in the absence of inhibitor. Twenty-two hours after in vitro maturation the determination of PI3K activity of oocytes by Western blot was performed using anti-PI3K subunit P85 antibody/peroxidase. The activity quantification was performed by densitometry of the bands using the Gel Perfect software (Bozzo and Retamal 1991 Arch. Biol. Med. Exp. 63, 510). To check the effect of treatment on energy metabolism, glucose and glycogen concentration of oocytes was quantified by Glucox 500 test (Doles Reagentes e Equipamentos Para Laboratórios Ltd., Goiânia, Brazil). The oocyte viability determination was performed by double labelling with propidium iodide and calcein AM. To determine the nuclear maturation, the oocytes were stained with 2% acetic orcein, being considered matured those with chromosomes in metaphase plate. To assess the meiotic spindle organisation, the oocytes were labelled with anti-α tubulin-FITC and propidium iodide. The distribution of actin filaments and mitochondria was determined by rhodamine-phalloidin labelling. The distribution of cortical granules was observed by labelling the oocytes with Lens culinaris–fluorescein isothiocyanate (FITC). The cleavage and blastocyst rates were determined at 48 and 168 h post-fertilization, respectively, both calculated on the number of oocytes placed to mature. The treatment means were compared by t-test (SAS Institute Inc., Cary, NC, USA, 2003). Wortmannin produced a reduction around 40% of PI3K activity; however, the levels of glucose and glycogen were not altered. No changes were found in the viability of in vitro matured oocytes or in nuclear maturation rate (P ≥ 0.05). Treatment did not promote any change in the organisation of meiotic spindle, distribution of actin filaments, and positioning of mitochondria. However, oocytes treated with wortmannin showed a significant increase (P ≤ 0.05) in the migration of cortical granules compared with controls (87.4% ± 11.4 and 72.8 ± 11.8%, respectively). The cleavage rate was not influenced by treatment, but the blastocyst rate was higher when oocytes were matured in presence of wortmannin (34.2 ± 6.4% v. 20.0 ± 5.0%, respectively; P ≤ 0.05). The results indicate that partial inhibition of PI3K activity in bovine oocytes treated with wortmannin during in vitro maturation did not affect nuclear maturation, but improved the migration of cortical granules, which seems to have contributed to the increased the blastocyst rate.

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This study aimed to determine the effect of presence of the corpus luteum (CL) and its influence on cumulus-oocyte complexes (COCs) obtained from the ipsilateral or contralateral ovary in bovine on the recovery and capacity of the oocytes to sustain mono-spermic fertilization, undergo preimplantation development, and develop to the blastocyst stage. Ovaries were collected at a local slaughterhouse and kept in pairs corresponding to the same animal. In the first experiment the variables evaluated were compared between cows with (CCL + ) and without (CCL -) CL, and for the second experiment, comparisons were made between ovaries with an ipsilateral (CL + ), contralateral (CL − ), and no (NCL). The recovery rate of COCs was higher in ovaries from CCL − cows, and a higher proportion of grade 1 COCs were recovered from this group. A higher proportion of metaphase I oocytes at 7 h of maturation, and a higher rate of cleavage were observed in the CCL + group; however, a higher proportion of embryos were obtained from the CCL − group. Besides, COCs from the CL + group had a lower proportion of grades 1 and 2 morphological qualities, lower rate of metaphase II oocytes at 22 h of maturation, and lower rate of formation of two pronuclei, whereas a higher proportion of unfertilized oocytes after in vitro fertilization. On the other hand, the COCs from the CL − group displayed a lower proportion of oocytes with more than two pronuclei, higher cleavage rate, and higher final blastocyst production were obtained when compared to CL+. Thus, the effects of CL on the competence of bovine COCs are different depending on the anatomical proximity of their location in the animal, negatively affecting the quality of COCs located in the same ovary, but not having negative effects on the competence of COCs in the ovaries contralateral to their location.

MOGOLLÓN-WALTERO, E.M. et al. Superovulação de fêmeas Nelore utilizando FSH veiculado em uma matriz polimérica biodegradável de liberação controlada em aplicação única. PUBVET, Londrina, V. 6, N. 30, Ed. 217, Art. 1447, 2012 PUBVET, Publicações em Medicina Veterinária e Zootecnia. Superovulação de fêmeas